Methods and systems for etching silicon cyanide (sicn) with multi-color selectivity

A system for processing a substrate, comprising:

• a processing chamber configured to receive the substrate having a multi-line layer formed thereon, the multi-line layer including a region having a pattern of alternating lines of a plurality of materials, wherein each line has a horizontal thickness, a vertical height, and extends horizontally across an underlying layer, wherein each line of the pattern of alternating lines extends vertically from a top surface of the multi-line layer to a bottom surface of the multi-line layer;
• and
• a controller coupled to the processing chamber and configured to control operations of the processing chamber to cause the processing chamber to:
• form a patterned recess in the multi-line layer to expose at least a first component of the multi-line layer and a second component of the multi-line layer, wherein at least one of the first component and the second component comprises a low-k material;
• and
• etch the first component with a non-corrosive etch process that is selective to the second component, wherein the non-corrosive etch process comprises etching the first component in an environment comprising a gaseous mixture of nitrogen trifluoride (NF3) and at least one diluent component.